The Animal Resources Core, to be led by Mollie Bloomsmith, PhD, will ensure that all animals selected for the Program Project meet the entrance criteria developed jointly by the Program Project investigators. In addition, members of the Core will monitor the status of the subjects throughout the grant period to ensure their continued appropriateness. The nonhuman primate subjects will be obtained from the YNPRC colony which maintains a valuable resource of rhesus macaques and chimpanzees of appropriate age classes for this research. Veterinary care will be supplied to promote health of the subjects and to manage the experimental procedures included in the Program Project. Environmental enrichment, socialization, and animal training programs will be applied to promote the psychological well-being of the nonhuman primate subjects in these studies, and to facilitate the conduct of high quality research with this important population. The specific aims of the Animal Resources Core are to: (1) Review the health and experimental records of all animal subjects prior to assignment, to determine if they meet the selection criteria described below, (2) review the health status of all monkeys and chimpanzees in the Program Project on a regular basis, perform routine clinical examinations including blood analyses and ophthalmologic examinations, and insure that the continued use of individual animals by the Program Project is appropriate, (3) coordinate the assignment of monkeys and chimpanzees to specific research projects, so as to avoid scheduling conflicts between users in the Program Project, (4) promote the psychological well-being of all monkeys and chimpanzees in the Program Project by providing'environmental enrichment to minimize behavioral problems, coordinate the socialization of subjects with their research use, and train animals to cooperate with experimental procedures using positive reinforcement techniques, (5) review results of postmortem autopsies and pathological surveys to determine whether undiagnosed health problems were present, the nature of which would warrant exclusion from the data analyses, (6) ensure prompt, thorough, and efficient access to all veterinary and animal-history records required by members of the Program Project, and, (7) ensure adequate oversight of anesthesia and documentation of recovery for designated experimental procedures.